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Whilst the benefits of agroforestry are widely recognised in tropical latitudes few studies have assessed how agroforestry is perceived in temperate latitudes. This study evaluates how stakeholders and key actors including farmers, landowners, agricultural advisors, researchers and environmentalists perceive the implementation and expansion of agroforestry in Europe. Meetings were held with 30 stakeholder groups covering different agroforestry systems in 2014 in eleven EU countries (Denmark, France, Germany, Greece, Hungary, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom). In total 344 valid responses were received to a questionnaire where stakeholders were asked to rank the positive and negative aspects of implementing agroforestry in their region. Improved biodiversity and wildlife habitats, animal health and welfare, and landscape aesthetics were seen as the main positive aspects of agroforestry. By contrast, increased labour, complexity of work, management costs and administrative burden were seen as the most important negative aspects. Overall, improving the environmental value of agriculture was seen as the main benefit of agroforestry, whilst management and socio-economic issues were seen as the greatest barriers. The great variability in the opportunities and barriers of the systems suggests enhanced adoption of agroforestry across Europe will be most likely to occur with specific initiatives for each type of system.  相似文献   
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Two hundred and fifteen Estrela Mountain Dogs (EMD) were examined using the PennHIP method between 2002 and 2006. Passive hip laxity (PHL) was estimated calculating the distraction index (DI). Pedigree information was obtained from the Portuguese Kennel Club. The heritability and breeding values were estimated using the linear Animal Model. The DI, using as reference the worst joint of each animal, ranged from 0.15 to 1.12 (0.55 +/- 0.19). The PHL was equal in right and left sides, and was higher in females than in males (P > 0.05 and P <0.01 in the t-test, respectively). The estimated heritability was 0.83 +/- 0.11. The mean breeding values for PHL were stable in EMD born between 1991 and 2003, and showed an improvement in 2004 and 2005. The data confirm high PHL in breeds with high prevalence and severity of canine hip dysplasia. The high heritability indicates that the DI could be reduced in the breed if PHL were used as a selection criterion. The early favourable evolution of DI breeding values could be related with the increase of voluntary radiographic hip screening in the last years, and the subsequent introduction of hip quality as a breeding criterion.  相似文献   
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Until now, no analytical method, not even isotopic ones, had been able to differentiate between sugars coming from C4-metabolism plants (cane, maize, etc.) and some crassulacean acid metabolism plants (e.g., pineapple, agave) because in both cases the isotope distributions of the overall carbon-13/carbon-12 and site-specific deuterium/hydrogen isotope ratios are very similar. Following recent advances in the field of quantitative isotopic carbon-13 NMR measurements, a procedure for the analysis of the positional carbon-13/carbon-12 isotope ratios of ethanol derived from the sugars of pineapples and agave using the site-specific natural isotopic fractionation-nuclear magnetic resonance (SNIF-NMR) method is presented. It is shown that reproducible results can be obtained when appropriate analytical conditions are used. When applied to pineapple juice, this new method demonstrates a unique ability to detect cane and maize sugar, which are major potential adulterants, with a detection limit in the order of 15% of the total sugars, which provides an efficient mean of controlling the authenticity of juices made from this specific fruit. When applied to tequila products, this new method demonstrates a unique ability to unambiguously differentiate authentic 100% agave tequila, as well as misto tequila (made from at least 51% agave), from products made from a larger proportion of cane or maize sugar and therefore not complying with the legal definition of tequila.  相似文献   
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Biodegradable films from isolate of sunflower (Helianthus annuus) proteins   总被引:1,自引:0,他引:1  
The film-forming potential of isolate of sunflower proteins (ISFP) was investigated. Homogeneous films were obtained by dissolution of ISFP in alkaline water (pH 12), addition of a plasticizer, casting, and drying. Maximum protein solubilization and unfolding led to films with the highest elasticity. The effects of five dissolving bases and five plasticizers on the mechanical properties were studied. The use of ionic bases (LiOH, NaOH) capable of interfering with the interproteic noncovalent bonds resulted in the greatest tensile strength (sigma(max)) and elongation at break (epsilon(max)) values (3.9 MPa and 215-251%, respectively). Plasticizers conferred diverse tensile properties to the films: the use of 1,3-propanediol resulted in the highest sigma(max) (27.1 MPa), and glycerol resulted in the greatest epsilon(max) (251%). Different mechanical properties were obtained by using mixtures of these plasticizers.  相似文献   
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Wheat gluten films were cast from aqueous dispersions containing 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as cross-linking reagents and glycerol as a plasticizer. Cross-linking was carried out to improve film properties such as water sensitivity and tensile strength. Films were characterized by measuring protein and water content, amount of amino groups, swelling of the films in water, and mechanical properties such as tensile strength (σmax) and strain at maximum stress ( at σmax). The use of different ratios of EDC to COOH resulted in different tensile properties and different percentage of swelling, which was attributed to the degree of cross-linking in the film. At a ratio of EDC/NHS/COOH=0.5/0.5/1, films had a water content of 10–11.5% and showed the highest σmax (2.8±0.9 MPa), the lowest at σmax (142±67%), and the lowest swelling (46%) compared to σmax=1.7±0.4 MPa, at σmax=257±63%, and swelling=68% for native gluten films.  相似文献   
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Milk somatic cell count is an indicator trait for mastitis resistance. Genetic parameters for somatic cell score in the Portuguese Holstein-Friesian population were estimated by modeling the pattern of genetic correlation over the first 3 lactations (days in milk) with a random regression model. Data records from the first 3 lactations were from the national database of the Portuguese Holstein Association herds. Heritability estimates ranged from 0.05 at the beginning of the lactation for the 3 lactations, to 0.07 at the end of the lactation period for the first and third lactations, to 0.09 for the second lactation. This increase in the heritability values was due to an increase in the genetic variance and a decrease in the residual variances. Genetic correlations evaluated for monthly time points were high (0.65 to 0.99) for all 3 lactations, whereas phenotypic correlations were much less than the genetic correlations (0.13 to 0.62).  相似文献   
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